package tk.mybatis.springboot.commons.utils;

import java.security.MessageDigest;

public class MD5Util
{
    public static final String MD5(String s)
    {
        char[] hexDigits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
        try
        {
            byte[] btInput = s.getBytes();

            MessageDigest mdInst = MessageDigest.getInstance("MD5");

            mdInst.update(btInput);

            byte[] md = mdInst.digest();

            int j = md.length;
            char[] str = new char[j * 2];
            int k = 0;
            for (int i = 0; i < j; i++)
            {
                byte byte0 = md[i];
                str[(k++)] = hexDigits[(byte0 >>> 4 & 0xF)];
                str[(k++)] = hexDigits[(byte0 & 0xF)];
            }
            return new String(str);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
        return null;
    }

    public static String MD5(String s, String salt)
    {
        String raw;
        if (StringUtil.isBlank(salt)) {
            raw = s;
        } else {
            raw = s + salt;
        }
        return MD5(raw);
    }

    private static String byteArrayToHexString(byte[] b)
    {
        StringBuffer resultSb = new StringBuffer();
        for (int i = 0; i < b.length; i++) {
            resultSb.append(byteToHexString(b[i]));
        }
        return resultSb.toString();
    }

    private static String byteToHexString(byte b)
    {
        int n = b;
        if (n < 0) {
            n += 256;
        }
        int d1 = n / 16;
        int d2 = n % 16;
        return hexDigits[d1] + hexDigits[d2];
    }

    public static String MD5Encode(String origin, String charsetname)
    {
        String resultString = null;
        try
        {
            resultString = new String(origin);
            MessageDigest md = MessageDigest.getInstance("MD5");
            if ((charsetname == null) || ("".equals(charsetname))) {
                resultString = byteArrayToHexString(md.digest(resultString.getBytes()));
            } else {
                resultString = byteArrayToHexString(md.digest(resultString.getBytes(charsetname)));
            }
        }
        catch (Exception localException) {}
        return resultString;
    }

    private static final String[] hexDigits = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };

    public static void main(String[] args)
    {
        System.out.println(MD5("1234"));
        System.out.println(MD5("1234", "hhhh"));
    }
}
